qemu-e2k/target
Michael Clark b02403363f
RISC-V: Workaround for critical mstatus.FS bug
This change is a workaround for a bug where mstatus.FS
is not correctly reporting dirty after operations that
modify floating point registers. This a critical bug
or RISC-V in QEMU as it results in floating point
register file corruption when running SMP Linux due to
task migration and possibly uniprocessor Linux if
more than one process is using the FPU.

This workaround will return dirty if mstatus.FS is
switched from off to initial or clean. According to
the specification it is legal for an implementation
to return only off, or dirty.

Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Sagar Karandikar <sagark@eecs.berkeley.edu>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Alex Bennée <alex.bennee@linaro.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-03-29 10:22:26 -07:00
..
alpha cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
arm target/arm: Always set FAR to a known unknown value for debug exceptions 2018-03-23 18:26:46 +00:00
cris cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
hppa target/hppa: Include priv level in user-only iaoq 2018-03-26 22:56:57 +08:00
i386 error: Strip trailing '\n' from error string arguments (again again) 2018-03-27 10:17:32 -05:00
lm32 cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
m68k -----BEGIN PGP SIGNATURE----- 2018-03-20 14:19:23 +00:00
microblaze cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
mips cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
moxie cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
nios2 cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
openrisc cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
ppc cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
riscv RISC-V: Workaround for critical mstatus.FS bug 2018-03-29 10:22:26 -07:00
s390x s390x/cpumodel: fix feature groups and breakage of MSA8 2018-03-23 09:05:42 +00:00
sh4 cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
sparc cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
tilegx cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
tricore cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
unicore32 cpu: get rid of unused cpu_init() defines 2018-03-19 14:10:36 -03:00
xtensa target/xtensa: fix timers test 2018-03-26 14:17:04 -07:00